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521.
522.
Juan S. Rocha-Ortiz Jianchang Wu Jonas Wenzel Andreas J. Bornschlegl Jose Dario Perea Salvador Leon Anastasia Barabash Anna-Sophie Wollny Dirk M. Guldi Jiyun Zhang Alberto Insuasty Larry Lüer Alejandro Ortiz Andreas Hirsch Christoph J. Brabec 《Advanced functional materials》2023,33(44):2304262
Dumbbell-shaped systems based on PAHs-BODIPY-triarylamine hybrids TM-(01-04) are designed as novel and highly efficient hole-transporting materials for usage in planar inverted perovskite solar cells. BODIPY is employed as a bridge between the PAH units, and the effects of the conjugated π-system's covalent attachment and size are investigated. Fluorescence quenching, 3D fluorescence heat maps, and theoretical studies support energy transfer within the moieties. The systems are extremely resistant to UVC 254 nm germicidal light sources and present remarkable thermal stability at degradation temperatures exceeding 350 °C. Integrating these systems into perovskite solar cells results in outstanding power conversion efficiency (PCE), with TM-02-based devices exhibiting a PCE of 20.26%. The devices base on TM-01, TM-03, and TM-04 achieve PCE values of 16.98%, 17.58%, and 18.80%, respectively. The long-term stability of these devices is measured for 600 h, with initial efficiency retention between 94% and 86%. The TM-04-based device presents noticeable stability of 94%, better than the reference polymer PTAA with 91%. These findings highlight the exciting potential of dumbbell-shaped systems based on PAHs-BODIPY-triarylamine derivatives for next-generation photovoltaics. 相似文献
523.
Anastasia Kerbs Arthur Burgardt Kareen H. Veldmann Dipl.-Ing. Thomas Schäffer Prof. Dr. Jin-Ho Lee Prof. Dr. Volker F. Wendisch 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200007
The aromatic amino acid l -tryptophan serves as a precursor for many valuable compounds such as neuromodulators, indoleamines and indole alkaloids. In this work, tryptophan biosynthesis was extended by halogenation followed by decarboxylation to the respective tryptamines or cleavage to the respective indoles. Either the tryptophanase genes tnaAs from E. coli and Proteus vulgaris or the aromatic amino acid decarboxylase genes AADCs from Bacillus atrophaeus, Clostridium sporogenes, and Ruminococcus gnavus were expressed in Corynebacterium glutamicum strains producing (halogenated) tryptophan. Regarding indoles, final titers of 16 mg L−1 7-Cl-indole and 23 mg L−1 7-Br-indole were attained. Tryptamine production led to a much higher titer of 2.26 g L−1 upon expression of AADC from B. atrophaeus. AADC enzymes were shown to be active with halogenated tryptophan in vitro and in vivo and supported production of 0.36 g L−1 7-Br-tryptamine with a volumetric productivity of 8.3 mg L−1 h−1 in a fed-batch fermentation. 相似文献
524.
Dr. Jorge Martinez-Garcia Benjamin Fenk Damian Gwerder David Schiffmann William Delgado-Diaz Dr. Anastasia Stamatiou Prof. Dr. Ludger J. Fischer Prof. Dr. Philipp Schuetz 《化学,工程师,技术》2023,95(5):792-796
X-ray computed tomography (XCT) combined with computational fluid dynamics (CFD) simulations have proved to be a powerful and versatile tool to describe fluids flow through packed bed systems. In this contribution, two examples of the application of XCT experiments to track the fluid flow and fluid penetration in packed bed systems are shown. The first one shows how geometrical information extracted from XCT measurements can be coupled to CFD simulations to assess fluid flows reliably. Here the example of a packed bed of three-dimensional (3D) printed cylindrical-shaped particles is considered. Finally, a short case study on the monitoring of the progress of the water penetration front in a packed bed composed of glass spheres using four-dimensional (4D) XCT imaging data is presented. 相似文献
525.
Julia R. Shakirova Vadim A. Baigildin Anastasia I. Solomatina Reza Babadi Aghakhanpour Vladimir V. Pavlovskiy Vitaly V. Porsev Sergey P. Tunik 《Advanced functional materials》2023,33(10):2212390
Herein, a novel pH-responsive phosphorescent probe based on cyclometalated iridium(III) complex is reported. To prevent oxygen quenching of phosphorescence and to improve the probe biocompatibility, the complex is covalently conjugated with a water-soluble block-copolymer that also increases its pH sensitivity. The resulting polymeric nanoprobe demonstrates a strong response of the phosphorescence lifetime onto pH variations in physiological range. Cellular experiments with Chinese hamster ovary (CHO-K1) cells show the predominant internalization of the probe in acidified cell compartments, endosomes and lysosomes. The analysis of phosphorescence lifetime imaging microscopy data confirms applicability of the sensor for monitoring of intra- and extracellular pH in cell cultures. 相似文献
526.
527.
Martin Reder Jana Holland-Cunz Paula Lorson Anastasia August Britta Nestler 《Advanced Engineering Materials》2023,25(19):2300340
Metal foams constitute a promising and emerging material class in the context of lightweight construction. There exists a variety of different foam topologies, on which resulting mechanical properties depend. To maximize the potential of foams in material use under mechanical load, the present work addresses the question how different geometrical parameters influence the material behaviour. Therefore, an algorithm for digital generation and design of open pore foam structures is presented, that allows to regulate the geometry precisely. A method for retrieving effective mechanical properties from numerical simulations of compression tests in the elastic regime is introduced. Additionally, the representativeness of foam volumes considered for simulations is investigated. This yields a fully digital workflow, which enables the investigation of geometry influence on mechanical properties. This approach is used to conduct simulation studies on generated foam structures with a systematic variation of geometrical parameters. Herein, a range of effective Young's moduli varying by up to a factor of 1.3 for different foam structures at the same porosity is found. This shows a significant impact of the foam geometry on the elastic properties of metal foams. The presented methodology yields insights, which can guide design and optimization of materials for specific applications. 相似文献
528.
Anastasia Kucheryavaya Zoltán Lenčéš Pavol Šajgalík Harald Harmuth 《International Journal of Applied Ceramic Technology》2023,20(2):541-562
Zirconium oxycarbides and zirconium oxycarbonitrides are high-temperature ceramic materials with great potential for applications in advanced technologies due to their good refractoriness, mechanical and thermoelectric properties, and corrosion resistance. The properties of ZrCO(N) materials strongly depend on their composition. However, the stoichiometry of stable ZrCO(N) compounds, synthesis chemistry, and thermodynamics of the proceeding reactions require clarification. This review comprehensively interprets data for ZrCO and ZrCON ceramics, including studies that may not have been addressed in prior reviews. It summarizes the state-of-the-art synthesis procedures involving reactions between commonly used zirconia, zirconium carbide, and carbon black, along with other zirconium sources widely used in the last few decades for the preparation of ZrCO(N) materials. The controversial reaction mechanisms of carbothermal reduction of zirconia and the role of CO gas in this process are discussed. The properties of ZrCO and ZrCON and their possible applications are also summarized. 相似文献
529.
Filipa Mota Tamas Yelland Jennie A. Hutton Jennifer Parker Anastasia Patsiarika A. W. Edith Chan Andrew O'Leary Constantina Fotinou John F. Martin Ian C. Zachary Snezana Djordjevic Paul Frankel David L. Selwood 《Chembiochem : a European journal of chemical biology》2022,23(1):e202100463
Vascular endothelial growth factors (VEGFs) regulate significant pathways in angiogenesis, myocardial and neuronal protection, metabolism, and cancer progression. The VEGF-B growth factor is involved in cell survival, anti-apoptotic and antioxidant mechanisms, through binding to VEGF receptor 1 and neuropilin-1 (NRP1). We employed surface plasmon resonance technology and X-ray crystallography to analyse the molecular basis of the interaction between VEGF-B and the b1 domain of NRP1, and developed VEGF-B C-terminus derived peptides to be used as chemical tools for studying VEGF-B - NRP1 related pathways. Peptide lipidation was used as a means to stabilise the peptides. VEGF-B-derived peptides containing a C-terminal arginine show potent binding to NRP1-b1. Peptide lipidation increased binding residence time and improved plasma stability. A crystal structure of a peptide with NRP1 demonstrated that VEGF-B peptides bind at the canonical C-terminal arginine binding site. VEGF-B C-terminus imparts higher affinity for NRP1 than the corresponding VEGF-A165 region. This tight binding may impact on the activity and selectivity of the full-length protein. The VEGF-B167 derived peptides were more effective than VEGF-A165 peptides in blocking functional phosphorylation events. Blockers of VEGF-B function have potential applications in diabetes and non-alcoholic fatty liver disease. 相似文献